1. Field of the Invention
The present invention relates to a method for preparing polymers as well as to the novel polymers per se. Many of these polymers are especially, although not exclusively, suitable for use in substantially non-aqueous liquid cleaning product compositions.
2. Background of the Invention
It is well known that polymerization in solution can be performed in many different reaction media. It is convenient to regard these media as falling into two categories, namely aqueous and non-aqueous.
When the polymer solution is required in essentially non-aqueous form such as is necessary for preparing non-aqueous liquid cleaning products, then it is very inconvenient to prepare the polymer in an aqueous solvent. Moreover, polymers prepared in aqueous media introduce undesirable amounts of water into the final product. For example, if the polymer is prepared as a 50% aqueous solution, and is to be incorporated as 10% by weight of the final total composition, this would introduce 10% of water into the final product causing rapid degradation of water sensitive components such as bleaches, etc.
It is already known to polymerize monomers in non-aqueous solvents such as lower alcohols, ethers, esters, hydrocarbons, halogenated hydrocarbons, etc. However, these materials are usually toxic, inflammable and have a noxious odor. More importantly, they can have a deleterious effect on non-aqueous liquid cleaning products into which they are incorporated.
It is known that after preparation, polymers can be extracted from either aqueous and non-aqueous solvent media by evaporation, precipitation, spray-drying or like method but this is time-consuming and expensive.